Improving YZ bond, fit, appearance, wear

[Mark Jackson]

We have really refined the YZ post milling processes (with the help of Glidewell R&D). Thought I'd share:

1) Put disc in large ultrasonic for one minute after milling and brushing and blowing off dust. You'll be surprised how quickly the water looks like milk. Tons of residual dust and debris you thought came off is still there. Change water.

2) Cut out units, refine anatomy if desired, brush/blow and put in smaller ultrasonic for additional four minutes. Again, water will fill instantly with plumes of white debris and turn solid white. Change water after every cycle.

3) Microwave on low for four minutes

4) Dry under UV light & suction for one minute

5) Pigment under full vacuum for five minutes

6) Dry under UV and suction for ten minutes

7) Sinter

We are doing this for BruxZir as well as copings and frameworks. You'd be surprised how much junk is left on the zirconia after milling and cleaning the old way, and under SEM examination it almost looks like sandpaper, but the little bits and pieces aren't sintered solidly into place, which could be affecting bond strength of layered porcelain, and certainly affects smoothness of glaze, wear and fit to the die. Studies are being done, but even to the naked eye, or under normal lab magnification the difference is dramatic.

Seems like a lot of extra work, but it makes a huge difference in quality. This is what the latest evolution of the prep center looks like. I've shared pictures in the past as this have changed..

 

[Hary]

Thanks for the info. Marc.

 

[DMC]

Thanks for sharing Betty Crocker.
I love your Chocholate cake frosting!

Wouldn't you think you are also tickling out some of the good pieces of Zirconia as well with the water and ultra-sonic? I would imagine you are doing as much harm as you are good. No?

Why not just take care of it after sintering, like with a sandblaster, or fine diamond? We have to use an ultra fine Komet diamond on Bruxzir to give Ultra fine horizontal texture for glaze. Also double checking contacts and occlusion.

If it's not truely sticking to the base Zirconia, it should just fall right off after the sintering with something, right? Like a simple sandblaster?

I find the Zirconia is just too rough out of the mill to simply glaze. We feel the need to smooth the Zirconia mechanically by hand. Colors are just a matter of playing with stains and staining technique. How you dry, and on what surface you are placing the copings/full anatomy.


I will try your method just for fun Mark.

 

[Bobby Orr ceramics]

Thanks for sharing Mark !! Money advice !!!

Stanley Cup (Orr)

 

[Mark Jackson]

I will try your method just for fun Mark.

Wish I could take credit. I have been working with the R&D folks at Glidewell and they showed me the SEM photographs of the various methods thay have tried, as well as actual samples of them, and the differncc was startling enough to integrate here immediately.

The nice thing about labs like Glidewell doing super high tech R&D is they take it way past where the manufacturer stops.

Their goals are different (consistency, reduced costs and improved quality of the end product) and therefore more in alignment with my own.

 

[NicelyMKV]

Nice post Mark. I realized awhile back that most of the substructures I was getting back had a fine sintered slurry coating over them?... I did not notice it at 1st until one day under the scope I noticed a different sheen in one small spot. Took a green wheel and lightly went over the coping and sure enough there was a light hard crust over it. I assumed it was slurry dust from the mill that was sintered along with the substructure. From that day on, any sub I received from anyone got a once over with a sintered diamond wheel and then lightly sandblasted, ultrasonic and ran through a regeneration firing in the furnace. I noticed i was not having any of the issues some people were with bond failures etc. Sounds like that may have been some of the issue.

Jason

 

[disturbed]

Thanks for sharing Mark !! Money advice !!!

Stanley Cup (Orr)

EXACTLY.....